For example, a solid polymer electrolyte fuel cell employs a membrane electrode assembly (MEA) which includes an electrolyte membrane of a polymer ion exchange membrane, an anode provided on one side of the electrolyte membrane, and a cathode provided on the other side of the electrolyte membrane. The membrane electrode assembly is sandwiched between a pair of separators to form a power generation cell. In use, in the fuel cell, generally, a predetermined number of power generation cells are stacked together to form a fuel cell stack, e.g., mounted in a fuel cell vehicle (fuel cell electric vehicle, etc.).
In the fuel cell, a fuel gas flow field for supplying a fuel gas along the anode and an oxygen-containing gas flow field for supplying an oxygen-containing gas along the cathode are provided in the surfaces of the separators. Further, a coolant flow field for supplying a coolant is provided between the adjacent separators along surfaces of the adjacent separators.
In the fuel cell, so called internal manifold type fuel cell has been adopted. In the internal manifold type fuel cell, fuel gas passages, oxygen-containing gas passages, and coolant passages extend through the fuel cells in the stacking direction for allowing the fuel gas, the oxygen-containing gas, and the coolant to flow through the fuel cell. The fuel gas passages (reactant gas passages) are a fuel gas supply passage and a fuel gas discharge passage. The oxygen-containing gas passages (reactant gas passages) are an oxygen-containing gas supply passage and an oxygen-containing gas discharge passage. The coolant passages are a coolant supply passage and a coolant discharge passage. In the fuel cell, at least one of the end plates is equipped with a fluid manifold member connected to each passage for supplying or discharging fluid (fuel gas, oxygen-containing gas, or coolant).
In the above in-vehicle fuel cell stack, various types of mount structures for mounting the fuel cells in the vehicle have been proposed, in order to protect the fuel cells and attach the fuel cells to the vehicle. For example, an in-vehicle fuel cell disclosed in Japanese Laid-Open Patent Publication No. 2006-040753 and a fuel cell system for a movable body disclosed in Japanese Laid-Open Patent Publication 2004-127787 are known.
Further, in the in-vehicle fuel cell stack, it is necessary to suitably protect the fuel cells against external loads such as vibrations or impacts during traveling of the vehicle. For example, a fuel cell installation structure disclosed in Japanese Laid-Open Patent Publication No. 2007-317406 is known. In this fuel cell installation structure, a fuel cell stack formed by stacking a plurality of power generation cells is supported at an installation position using a cushioning device. The cushioning device has a conversion function for converting the direction of external force in a direction intersecting with the stacking direction of the power generation cells of the fuel cell stack into the stacking direction of the power generation cells.
In the structure, when an external force is applied to the fuel cell stack in a direction perpendicular to the stacking direction of the power generation cells, the direction of this external force is converted into the stacking direction of the power generation cells in which the durability against the external force is relatively high. According to the disclosure, by this structure, improvement of the vibration resistance and impact resistance is achieved.